Seeing that for 45 years HBO was boxing's top network, is/was the marquee brand HBO just as well known around the globe for boxing as the big 4 sanctioning bodies?
The sanction bodies are well known?! Sure us boxing nerds use them in everyday speak, but the casual fancy does not really care. Hence our frustration sometimes, as the casual fan generally thinks a world title fight is a world title fight; they do not care about the sanctioning body or even the lineage of the title.
Tony Soprano, undefeated HBO heavyweight champion of the weeerld, can just hear Buffer at his belllowing best!
I concur with the responses here, there's really no comparison between a broadcaster and sanctioning bodies. A better comparison would be to ask if the Ring Magazine rankings and belts are on par with the alphabets.